In the past year, our core has assisted NHLBI investigators in successfully generating more than one dozen transgenic and knockout mouse lines. One new capability our core has established during this year is the generation of targeted transgenic mouse lines, which is to insert a transgene into a specific genomic locus by co-injecting the transgene with the Phi31 recombinase into the pronuclei of fertilized eggs. We have also succeeded in deriving mouse embryonic stem cell (ESC) and epistem cell (EpiSC) lines from early mouse embryos. Our core has also devoted a substantial portion of our efforts on developing induced pluripotent stem cell (iPSC) related capabilities. We have gained a broad range of skills in this area, including iPSC derivation, random differentiation through embroid body formation and teratoma formation, karyotyping, and directed differentiation into cardiomyocyte and neuronal lineage. We have assisted several laboratories in deriving a number of mouse iPSC lines, and succeeded in deriving iPSC lines from a GFP-expressing transgenic pig. We have also succeeded in targeting reporter genes into a safe harbor locus (AAVS1) of human iPSCs derived from NIH patients. We aslo microinjected mouse iPSCs and hematopoietic stem cells (HSCs) into blastocysts collected from a knockout mouse strain, which is incapable of forming blood lineage. Throughout the year, we have provided numerous consultations and technical assistances to scientists with in and out of NHLBI to assist them in conducting mouse molecular genetic research, including designing DNA constructs, searching database, collecting various stages of embryos, deriving mouse embryonic fibroblasts (MEF), collecting mouse organs, and reconstituting mouse lines using cryopreserved sperm. I am also a member of the NHLBI Animal Care and Use Committee (ACUC) for reviewing animal protocols and conducting animal facility inspections.